Convenient One-pot Access to Pyrano[2,3-d]pyrimidine Derivatives via a CuCl2.2H2O Catalyzed Knoevenagel-Michael Addition Reaction in Water/Ethanol Media

Abstract

Convenient procedure for the synthesis of corresponding pyrano[2,3-d]pyrimidine derivatives were developed via one-pot three-component reaction of aryl aldehyde derivatives, malononitrile with barbituric acids in the presence of copper (II) chloride dihydrate (CuCl2.2H2O) as highly efficient Lewis acid catalyst. This protocol has advantages such as readily and inexpensive catalyst, high reaction yields, eco-friendly solvent and high atom-economy.